Seminários

Seminários do IF-UFF

Gostaria de convidar a todos para um seminário sobre Magnetismo Molecular que acontecerá nessa Sexta-Feira 14/11/2014 na Sala A2-07, às 14hs.

Palestrante: Marius Andruh (Universidade de Bucharest - Romênia)

Título: Molecular nano-magnets: new synthetic approaches

Abstract:
The last twenty years or so, Molecular magnetism is dominated by the so-called nano-magnets, which are 0-D or 1-D molecular edifices (Single Molecule Magnets, SMMs, and Single Chain Magnets, SCMs). Such systems exhibit a magnetic hysteresis and slow relaxation of magnetization, which arises from a high spin ground state and a strong uniaxial (Ising type) magnetic anisotropy. In order to fulfill these two conditions, with the ultimate goal of rising the blocking temperatures, chemists are seeking new synthetic strategies leading to molecular nano-magnets. The high interest in SMMs and SCMs arises from their potential applications in quantum computing, spintronics and high-density memory devices.1
        We currently develop new synthetic strategies leading to SMMs and SCMs, which are based on the combination of three different spin carriers (nd and 4f transition metal ions, as well as 2p or 3p radicals).2 The very first SCMs containing three different paramagnetic metals have been synthesized in our laboratory. The synthetic approach consists of self-assembly processes involving high spin anisotropic oligonuclear complexes (nodes) and various metalloligands (spacers). Other recent systems (2p-3d-4f) will be presented as well. A special emphasis is given to the extension of these strategies towards molecular refrigerants (compounds with a significant magneto-caloric effect) and towards new luminescent molecular materials based on lanthanides.

1 See for example: (a) X. Feng, T. David Harris, J. R. Long, Chemical Science 2011, 2, 1688; (b) R. Clérac, H. Miyasaka, M. Yamashita, C. Coulon, J. Am. Chem. Soc. 2002, 124, 12837; (c) A. Cornia, M. Mannini, P. Sainctavit, R. Sessoli, Chem. Soc. Rec. 2011, 40, 3076.
2 See, for example: (a) A. M. Madalan, H. W. Roesky, M. Andruh, M. Noltemeyer, N. Stanica, Chem. Commun. 2002, 1638; (b) T. D. Pasatoiu, M. Etienne, A. M. Madalan, M. Andruh, R. Sessoli, Dalton Trans., 2010, 39, 4802; R. Gheorghe, A. M. Madalan, J.-P. Costes, W. Wernsdorfer, M. Andruh, Dalton Trans., 2010, 39, 4734; D. Visinescu, A. M. Madalan, M. Andruh, C. Duhayon, J.-P. Sutter, L. Ungur, W. Van den Heuvel, L. F. Chibotaru, Chem.-Eur. J., 2009, 15, 11808; L. B. L. Escobar, G. P. Guedes, S. Soriano, N. L. Speziali, A. K. Jordão, A. C. Cunha, V. F. Ferreira, C. Maxim, M. A. Novak, M. Andruh, M. G. F. Vaz, Inorg. Chem., 2014, 53, 7508.